"or ""quijicha guexica"" (""grandfather's foot""). At the equinoxes of March and September, the Sun rises in the valley right between the two hills. Chía and Sué formed the basis of the complex Muisca calendar, where synodic and sidereal months were taken into account in three types of years; rural years of 12 or 13 months, common years of 20 months and holy years of 37 months. Weeks with weekly markets were 4 days, making every month 7 weeks. According to Duquesne, the Muisca used their 'perfect' number ""gueta""; a century consisted of 20 holy years (20 times 37 months; 740)"
"December 25. The September equinox takes place in this month, and certain observances are organized around it. It is the Autumn equinox in the Northern Hemisphere, and the Vernal Equinox in the Southern Hemisphere. The dates can vary from 21 September to 24 September (in UTC). September is mostly in the sixth month of the astrological calendar (and the first part of the seventh), which begins at the end of March/Mars/Aries. ""This list does not necessarily imply either official status or general observance."" September September is the ninth month of the year in the Julian and Gregorian calendars, the third"
"Equinox An equinox is commonly regarded as the instant of time when the plane (extended indefinitely in all directions) of Earth's equator passes through the center of the Sun. This occurs twice each year: around 21 March and 22–23 September. In other words, it is the moment at which the center of the visible Sun is directly above the Equator. In the northern hemisphere, the equinox in March is called the Vernal or Spring Equinox; the September equinox is called the Autumnal or Fall Equinox. However, because the Moon (and to a lesser extent the other planets) cause the motion"
"average, and can last a few weeks before and after the exact equinox. Saturn's most recent equinox was on 11 August 2009, and its next will take place on 6 May 2025. Mars's most recent equinox was on 22 May 2018 (northern autumn), and the next will be on 23 March 2019 (northern spring). Equinox An equinox is commonly regarded as the instant of time when the plane (extended indefinitely in all directions) of Earth's equator passes through the center of the Sun. This occurs twice each year: around 21 March and 22–23 September. In other words, it is the"
"""Nox"", meaning ""night"". In other words, the equinoxes are the only times when the subsolar point is on the equator, meaning that the Sun is exactly overhead at a point on the equatorial line. The subsolar point crosses the equator moving northward at the March equinox and southward at the September equinox. The equinoxes, along with solstices, are directly related to the seasons of the year. In the northern hemisphere, the vernal equinox (March) conventionally marks the beginning of spring in most cultures and is considered the start of the New Year in Hindu calendar and the Persian calendar or"
"March equinox The March equinox or Northward equinox is the equinox on the Earth when the subsolar point appears to leave the Southern Hemisphere and cross the celestial equator, heading northward as seen from Earth. The March equinox is known as the vernal equinox in the Northern Hemisphere and as the autumnal equinox in the Southern. On the Gregorian calendar, the Northward equinox can occur as early as 19 March or as late as 21 March. For a common year the computed time slippage is about 5 hours 49 minutes ""later"" than the previous year, and for a leap year"
"Vernal Equinox (Spring Equinox, when the day and the night is of equal length, set at March 21 in the Gregorian Calendar). It begins the first month, named Nisanu/Nisan/Abib. The month of Nisan is important since it begins the Spring Feasts of Israel. The observation of the New Moon may be influenced by the weather condition, so the Rosh Chodesh may be delayed for one or two days. But over all the errors cancel each other, and the calendar system remains accurate. The intercalary month could be a second Sixth Month (Ululu II), as often practiced in Mesopatamia, or a"
"end of summer and the beginning of autumn (autumnal equinox) in the Northern Hemisphere, while marking the end of winter and the start of spring (vernal equinox) in the Southern Hemisphere. The September equinox is one point in time commonly used to determine the length of the tropical year. Date and time of the September equinox that occurred from the year 2010 to 2018 (UT) are listed as follows: The point where the Sun crosses the celestial equator southwards is called the first point of Libra. However, due to the precession of the equinoxes, this point is no longer in"
"September equinox The September equinox (or Southward equinox) is the moment when the Sun appears to cross the celestial equator, heading southward. Due to differences between the calendar year and the tropical year, the September equinox can occur at any time from the 21st to the 24th day of September. At the equinox, at the equator, the Sun rises directly in the east and sets directly in the west. Before the Southward equinox, the Sun rises and sets more to the north, and afterwards, it rises and sets more to the south. The equinox may be taken to mark the"
"March equinox to the September equinox, and in the southwest quadrant from the September equinox to the March equinox. Sunsets occur almost exactly due west on the equinoxes for all viewers on Earth. Exact calculations of the azimuths of sunset on other dates are complex, but they can be estimated with reasonable accuracy by using the analemma. As sunrise and sunset are calculated from the leading and trailing edges of the Sun, respectively, and not the center, the duration of a daytime is slightly longer than nighttime (by about 10 minutes, as seen from temperate latitudes). Further, because the light"
"equinoxes shift through the constellations as follows (expressed in astronomical year numbering when the year 0 = 1 BC, −1 = 2 BC, etc.): The equinoxes are sometimes regarded as the start of spring and autumn. A number of traditional harvest festivals are celebrated on the date of the equinoxes. Observations of the equinox are frequently used in online debates between flat-earth conspiracy proponents and those who support the generally accepted heliocentric globe model. Wolfie6020, a well-known flat-earth debunker on YouTube, has a semi-annual Equinox Challenge with prizes available to any flat-earther who can show a functioning flat-earth model that"
"3 March, 21:18 (Julian). According to the sidereal solar calendar, celebrations which originally coincided with the vernal equinox now take place throughout South Asia and parts of Southeast Asia on the day when the Sun enters the sidereal Aries, generally around 14 April. March equinox The March equinox or Northward equinox is the equinox on the Earth when the subsolar point appears to leave the Southern Hemisphere and cross the celestial equator, heading northward as seen from Earth. The March equinox is known as the vernal equinox in the Northern Hemisphere and as the autumnal equinox in the Southern. On"
"those of Earth — after all, the two ecliptic planes only have a mutual inclination of 1.85° — but on Mars, the Sun spends 6 days in the constellation Cetus, leaving and re-entering Pisces as it does so, making a total of 14 zodiacal constellations. The equinoxes and solstices are different as well: for the northern hemisphere, vernal equinox is in Ophiuchus (compared to Pisces on Earth), summer solstice is at the border of Aquarius and Pisces, autumnal equinox is in Taurus, and winter solstice is in Virgo. As on Earth, precession will cause the solstices and equinoxes to cycle"
"an equinox marks the point in time when the sun has neither northern nor southern declination but is crossing the celestial equator. Of the two possible equinoxes the ancient Greeks chose the March equinox as the starting point. This coincided with the festival of Hilaria, a time of optimism and beginnings where farmers began to sow or observed the first growth/blossoming of trees and summer crops. The naming of Aries is late in the Babylonian zodiac where the equinox was in its earliest tradition marked as in the early Middle Bronze Age by actual coincidence with the Pleiades. The time"
"Equinoxes, when there is midnight sun at the South Pole. This period is also referred to as Pitrayana (with the Pitrus (i.e. ancestors) being placed at the South Pole). This festival is currently celebrated on 14 or 15 January but due to axial precession of the earth it will continue to shift away from the actual season. The season occurs based on tropical sun (without ayanamsha). The earth revolves around sun with a tilt of 23.45 degrees. When the tilt is facing the sun we get summer and when the tilt is away from the sun we get winter. That"
"summer solstice and shorter around the winter solstice. When the Sun's path crosses the equator, the length of the nights at latitudes +L° and -L° are of equal length. This is known as an equinox. There are two solstices and two equinoxes in a tropical year. The seasons occur because the Earth's axis of rotation is not perpendicular to its orbital plane (the plane of the ecliptic) but currently makes an angle of about 23.44° (called the obliquity of the ecliptic), and because the axis keeps its orientation with respect to an inertial frame of reference. As a consequence, for"
"saros occurred near March Equinox and even numbered saros occurring near September Equinox. During a minor lunar standstill, the moon was on the 18th parallel because eclipses of even numbered saros occurred near March Equinox and odd numbered saros occurred near September Equinox. Lunar standstill A lunar standstill is the gradually varying range between the northern and the southern limits of the Moon's declination, or the lunistices, over the course of one-half a sidereal month (about two weeks), or 13.66 days. (Declination is a celestial coordinate measured as the angle from the celestial equator, analogous to latitude.) One major, or"
"♈︎ the symbol for Aries, represents the March equinox; ♋︎, for Cancer, the June solstice; ♎︎, for Libra, the September equinox; and ♑︎, for Capricorn, the December solstice. Symbols for aspects and nodes appear in medieval texts, although medieval and modern usage of the node symbols differ; the modern ascending node symbol (☊) formerly stood for the descending node, and the modern descending node symbol (☋) was used for the ascending node. In describing the Keplerian elements of an orbit, ☊ is sometimes used to denote the ecliptic longitude of the ascending node, although it is more common to use"
"to seasonal lag the autumnal equinox is considerably warmer than the vernal equinox in most regions. However even with seasonal lag the autumnal equinox is cooler than the summer solstice in most regions as well as the vernal equinox being warmer than the winter solstice even in most oceanic areas. In eastern Canada the seasonal lag is consistent both in summer and winter, resulting in February and August being the coldest and warmest months, respectively. In Western Europe the lag is lower in spite of the Atlantic coastline, usually around a month, which is also consistent with many inland areas"
"A programming bug confusing these two year numbers is probably the cause of some Android users of Twitter being unable to log in around midnight of 29 December 2014 UTC. Solar astronomic phenomena, such as equinox and solstice, vary over a range of at least seven days. This is because each equinox and solstice may occur any day of the week and hence on at least seven different ISO week dates. For example, there are spring equinoxes on 2004-W12-7 and 2010-W11-7. The ISO week calendar relies on the Gregorian calendar, which it augments, to define the new year day (Monday"
"vernal equinox in UT always falling either on 20 or 21 March in the period of 1797 to 2043, falling on 19 March in 1796 the last time and in 2044 the next. Except for 2003 and 2007, the vernal equinox has started on 20 March since 1980, and is projected to until 2043. Because the Earth's axis is at an angle, some signs take longer to rise than others, and the farther away from the equator the observer is situated, the greater the difference. Thus, signs are spoken of as ""long"" or ""short"" ascension. The zodiac system was developed"
"March March is the third month of the year in both the Julian and Gregorian calendars. It is the second of seven months to have a length of 31 days. In the Northern Hemisphere, the meteorological beginning of spring occurs on the first day of March. The March equinox on the 20th or 21st marks the astronomical beginning of spring in the Northern Hemisphere and the beginning of autumn in the Southern Hemisphere, where September is the seasonal equivalent of the Northern Hemisphere's March. The name of March comes from ""Martius"", the first month of the earliest Roman calendar. It"
"interior translucent-or-opaque window quilts, drapes, shutters, movable trellises, etc. can be used for hourly, daily or seasonal sun and heat transfer control (without any active electrical air conditioning). Everywhere around the world during the equinoxes (March 20/21 and September 22/23) except for the poles, the sun rises due east and sets due west. In the Northern Hemisphere, the equinox sun peaks in the southern half (about halfway up from the horizon at mid latitude) of the sky, while in the Southern Hemisphere, that sun peaks in the northern half of the sky. When facing the equator, the sun appears to"
"tropics. From the March equinox to the September equinox, the Sun rises within 23.5° north of due east, and sets within 23.5° north of due west. From the September equinox to the March equinox, the Sun rises within 23.5° south of due east and sets within 23.5° south of due west. The Sun's path lies entirely in the northern half of the celestial sphere from the March equinox to the September equinox, but lies entirely in the southern half of the celestial sphere from the September equinox to the March equinox. On the equinoxes, the equatorial Sun culminates at the"
"(the paschal full moon). However, the vernal equinox and the full moon are not determined by astronomical observation. The vernal equinox is fixed to fall on 21 March (previously it varied in different areas and in some areas Easter was allowed to fall before the equinox). The full moon is an ecclesiastical full moon determined by reference to a lunar calendar, which again varied in different areas. While Easter now falls at the earliest on the 15th of the lunar month and at the latest on the 21st, in some areas it used to fall at the earliest on the"
"is in Pisces, while that on the September equinox is in Virgo (as of J2000). Along its yearly path through the zodiac, the Sun meets the celestial equator from south to north at the First Point of Aries, and from north to south at the First Point of Libra. The First Point of Aries is considered to be the celestial ""prime meridian"" from which right ascension is calculated. At first glance any of the equinoxes or solstices might seem to be likely candiates for marking the starting point of the sun's migration across celestial sphere. The equinoxes are preferred as"
"line of apsides of Earth's elliptical orbit. The orbital ellipse (with eccentricity exaggerated for effect) goes through each of the six Earth images, which are sequentially the perihelion (periapsis—nearest point to the sun) on anywhere from 2 January to 5 January, the point of March equinox on 19, 20 or 21 March, the point of June solstice on 20 or 21 June, the aphelion (apoapsis—farthest point from the sun) on anywhere from 4 July to 7 July, the September equinox on 22 or 23 September, and the December solstice on 21 or 22 December. These ""astronomical"" seasons are not of"
"plane, summer is from December to March and winter is from June to September. September 22 or 23 is the vernal equinox and March 20 or 21 is the autumnal equinox. The South Pole is in the center of the southern hemispherical region. Southern Hemisphere climates tend to be slightly milder than those at similar latitudes in the Northern Hemisphere, except in the Antarctic which is colder than the Arctic. This is because the Southern Hemisphere has significantly more ocean and much less land; water heats up and cools down more slowly than land. The differences are also attributed to"
"AU, mean equinox and ecliptic of date. This specifies the mean equinox of 4 Jan 2010 0h TT as above, without the addition of nutation. Because the orbit of the Moon is inclined only about 5.145° to the ecliptic and the Sun is always very near the ecliptic, eclipses always occur on or near it. Because of the inclination of the Moon's orbit, eclipses do not occur at every conjunction and opposition of the Sun and Moon, but only when the Moon is near an ascending or descending node at the same time it is at conjunction or opposition. The"
"moon referred to (called the Paschal full moon) is not an astronomical full moon, but the 14th day of a lunar month. Another difference is that the astronomical equinox is a natural astronomical phenomenon, which can fall on 19, 20 or 21 March, while the ecclesiastical date is fixed by convention on 21 March. In applying the ecclesiastical rules, Christian churches use 21 March as the starting point in determining the date of Easter, from which they find the next full moon, etc. The Eastern Orthodox and Oriental Orthodox Churches continue to use the Julian calendar. Their starting point in"
"the autumnal equinox and the vernal equinox; farther from the equator they happen closer to the winter solstice. Because it orbits relatively close to Mars, Deimos cannot be seen north of 82.7°N or south of 82.7°S; such latitudes will obviously not see transits either. On 4 March 2004, a transit was photographed by Mars Rover ""Opportunity"", while on 13 March 2004, a transit was photographed by Mars Rover ""Spirit"". In the captions below, the first row shows Earth time UTC and the second row shows Martian local solar time. The data in the tables below is generated using JPL Horizons."
"totality. For example, birds and squirrels return to their nests and crickets chirp. Eclipses only occur in the eclipse season, when the Sun is close to either the ascending or descending node of the Moon. Each eclipse is separated by one, five or six lunations (synodic months), and the midpoint of each season is separated by 173.3 days, which is the mean time for the Sun to travel from one node to the next. The period is a little less than half a calendar year because the lunar nodes slowly regress. Because 223 synodic months is roughly equal to 239"
"vernal equinox. The vernal equinox can be used as a principal direction for ECI frames. The Sun lies in the direction of the vernal equinox around 21 March. The fundamental plane for ECI frames is usually either the equatorial plane or the ecliptic. The location of an object in space can be defined in terms of right ascension and declination which are measured from the vernal equinox and the celestial equator. Right ascension and declination are spherical coordinates analogous to longitude and latitude, respectively. Locations of objects in space can also be represented using Cartesian coordinates in an ECI frame."